Nerve stimulation is used and/or proposed for use in treating certain medical conditions, including epilepsy, heart failure and tremor. Typically, an action potential that is artificially initiated at a site on an axon of the nerve (e.g., midway along a nerve), propagates in both directions (e.g., in orthodromic and antidromic directions) along the nerve. For some conditions, this precludes the use of nerve stimulation-based treatment, e.g., due to an undesired effect on an anatomical site (e.g., a non-target anatomical site) that is at the opposite end of the nerve to the anatomical site being treated (i.e., the target site).
In some cases, a blocking device is used to apply a blocking current behind the initiated action potential, so as to block the action potential from propagating to the non-target anatomical site.